Backrest adjusting mechanism and chair using same

ABSTRACT

This invention is a backrest adjusting mechanism and a chair using the same and relates to the technical field of chairs. The backrest adjusting mechanism has a backrest, and the backrest is movably arranged above a support surface of a chair body, and a distance between the backrest and a backrest support plate of the chair body is adjustable; the backrest is provided with a connecting base on a side close to the backrest support plate of the chair body. The backrest adjusting mechanism has at least one set of sliding assembly, wherein the sliding assembly is configured to connect the connecting base and the backrest support plate of the chair body.

CROSS-REFERENCE TO RELATED APPLICATIONS

This is a U.S. patent application which claims the priority and benefitof Chinese patent application number 202122236719.3, filed on Sep. 14,2021, the disclosure of which is incorporated herein by reference in itsentirety.

BACKGROUND OF THE INVENTION 1. Technical Field

This disclosure belongs to the technical field of chairs, and inparticular relates to a backrest adjusting mechanism and a chair usingthe same.

2. Description of Related Art

A backrest is used to support the back and waist of users when the usersare in a sitting posture A backrest support of an existing chair isusually fixed and immovable. The users can only make their back close tothe backrest by changing their sitting posture to achieve a support forthe back. It has certain limitations and limits the user's sittingposture. Therefore, a backrest adjusting mechanism and a chair using thesame are provided.

BRIEF SUMMARY OF THE INVENTION

In view of the shortcomings of the prior art, the objective of thisdisclosure is to provide a backrest adjusting mechanism and a chairusing the same to solve the problem put forward in the background.

The objective of this disclosure can be achieved by the followingtechnical solutions: a backrest adjusting mechanism includes a backrest,wherein the backrest is movably arranged above a support surface of achair body, and a distance between the backrest and a backrest supportplate of the chair body is adjustable; the backrest is provided with aconnecting base on a side close to the backrest support plate of thechair body, and the backrest is movably connected with the connectingbase;

The backrest adjusting mechanism further including at least one set ofsliding assembly, wherein the sliding assembly is configured to connectthe connecting base and the backrest support plate of the chair body,the sliding assembly includes a sliding block and a sliding rail, thesliding block is slidably connected with the sliding rail, the slidingblock is fixedly connected with the connecting base, the sliding rail isfixedly connected with the chair body, and the sliding rail is providedwith an anti-off component for limiting the sliding block from fallingoff;

The backrest adjusting mechanism further includes an elastic member,arranged between the connecting base and the backrest support plate ofthe chair body.

As a further solution of this disclosure, the elastic member includes aspring having an end fixedly engaged with the connecting base and an endfixedly engaged with an engaging block; a distance between the engagingblock and a cover plate is adjustable for adjusting a support force ofthe backrest, and the cover plate and the chair body are fixedlyconnected.

As a further solution of this disclosure, an adjusting rod is arrangedon the cover plate and rotatably connected with the cover plate, and theclamping block is in threaded connection with the adjusting rod.

As a further solution of this disclosure, the backrest adjustingmechanism further includes a locking mechanism, and the lockingmechanism is configured to fix the connecting base to keep a fixeddistance from the chair body.

A chair includes the backrest adjusting mechanism, wherein the backrestis slidably connected to the connecting base, the backrest movesvertically up and down along the connecting base, the connecting base isprovided with a height adjusting assembly, the height adjusting assemblyis configured to adjust a height of the backrest.

As a further solution of this disclosure, the height adjusting assemblyincludes a swing rod and a limit rod, a fan-shaped groove is formed in aside of the connecting base away from the backrest, and the swing rod isreceived in the fan-shaped groove. One end of the swing rod is hingedwith the connecting base, and a torsion spring is arranged at the hingedposition to keep the swing rod in a vertical state;

A groove is formed in a side of the backrest close to the connectingbase, a plurality of oblique tooth grooves are arranged in an array in avertical direction in the groove, the tooth groove direction of theoblique tooth grooves faces downward, and the limit rod is fixed on anend of the swing rod away from the hinged position, and extends throughthe connecting base to be inserted into one oblique tooth groove.

A chair includes the backrest adjusting mechanism, wherein the backrestis hinged with the connecting base through a pivot, the backrest swingsin a vertical plane along the connecting base within a set swing anglerange.

A chair includes the backrest adjusting mechanism, wherein the backrestis provided with a rotating shaft along a vertical direction, thebackrest and the connecting base is hinged through the rotating shaft.

This disclosure has the beneficial effects: the backrest and the chairbody are connected by the sliding assembly, and an elastic support isprovided by the elastic member so that the backrest is always fit withthe user's back and moves together with the user, thereby reducing theuser's fatigue and effectively alleviating waist fatigue of userssitting on the chair for a long time; moreover, by adjusting thecompression amount of the spring, the support force of the backrest canbe adjusted to meet the use needs of different users.

This disclosure discloses a backrest adjusting mechanism and a chairusing the same and relates to the technical field of chairs. Thebackrest adjusting mechanism comprises a backrest, wherein the backrestis movably arranged above a support surface of a chair body, and adistance between the backrest and a backrest support plate of the chairbody is adjustable; the backrest is provided with a connecting base on aside close to the backrest support plate of the chair body. The backrestadjusting mechanism further comprises at least one set of slidingassembly, wherein the sliding assembly is configured to connect theconnecting base and the backrest support plate of the chair body. Thebackrest adjusting mechanism further comprises an elastic member,arranged between the connecting base and the backrest support plate ofthe chair body. In this disclosure, the backrest and the chair body areconnected by the sliding assembly, and an elastic support is provided bythe elastic member so that the backrest is always fit with the user'sback and moves together with the user, thereby reducing the user'sfatigue and effectively alleviating waist fatigue of users sitting onthe chair for a long time.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWINGS

In order to more clearly illustrate the technical solutions in theembodiments of this disclosure or in the prior art, drawings to be usedfor describing the embodiments or the prior art will be introducedbriefly hereinafter. Obviously, those skilled in the art may alsoconclude other drawings based on these drawings without creativeefforts.

FIG. 1 is a schematic structural diagram of an overall structure of thisdisclosure;

FIG. 2 is a cross-sectional view of this disclosure;

FIG. 3 is a schematic structural diagram of a backrest of thisdisclosure;

FIG. 4 is a schematic structural diagram of a height adjusting mechanismof this disclosure; and

FIG. 5 is a schematic structural diagram of an internal connectingassembly of this disclosure;

In the figures, 1—backrest, 2—connecting base, 3—chair body, 4—limitpin, 5—spring, 6—engaging block, 7—adjusting rod, 8—cover plate,11—sliding block, 12—sliding rail, 101—groove, 102—oblique tooth groove,21—limit support, 22—swing rod, 211—fan-shaped groove, 221—limit rod,31—second sleeve, 201—first sleeve.

DETAILED DESCRIPTION OF THE INVENTION

The technical solutions in the embodiments of this disclosure will bedescribed clearly and completely below in connection with the drawingsin the embodiments of this disclosure, and it will be apparent that theembodiments described here are merely a part, not all of the embodimentsof this disclosure. According to the embodiments in this disclosure, allother embodiments obtained by those of ordinary skill in the art withoutcreative work fall within the scope of this disclosure.

Referring to FIGS. 1 to 5 , in embodiments of this disclosure, providedis a backrest adjusting mechanism, wherein a backrest 1 is movablyarranged above a support surface of a chair body 3, and a distancebetween the backrest 1 and a backrest support plate of the chair body 3is adjustable; the backrest 1 is provided with a connecting base 2 on aside close to the backrest support plate of the chair body 3, and thebackrest 1 is movably connected with the connecting base 2. The backrestadjusting mechanism further includes a sliding assembly, wherein thesliding assembly is configured to connect the connecting base 2 and thebackrest support plate of the chair body 3, the sliding assemblyincludes a sliding block 11 and a sliding rail 12, the sliding block 11is slidably connected with the sliding rail 12, the sliding block 11 isfixedly connected with the connecting base 2, the sliding rail 12 isfixedly connected with the chair body 3, and the sliding rail 12 isprovided with an anti-off component for limiting the sliding block 11from falling off; that is, the sliding fit between the sliding block 11and the sliding rail 12 ensures the smoothness of a telescopic movementbetween the connecting base 2 and the chair body 3, and in the meanwhilereduces the wear between the components. The sliding rail 12 is providedwith an anti-off block at an end position to prevent the sliding block11 from falling off.

The backrest adjusting mechanism further includes an elastic member,arranged between the connecting base 2 and the backrest support plate ofthe chair body 3.

In use, the backrest 1 supports the user's back; by the elastic member,the backrest 1 can always support the user's back. When the user's bodymoves, the backrest 1 moves together with the user's body, therebyalways supporting the user's back, reducing the user's fatigue, andeffectively alleviating waist fatigue of users sitting on the chair fora long time.

Preferably, the elastic member is configured as a spring 5, one end ofthe spring 5 is fixedly engaged with the connecting base 2, and theother end of the spring 5 is fixedly engaged with an engaging block 6. Adistance between the engaging block 6 and a cover plate 8 is adjustablefor adjusting a support force of the backrest 1, and the cover plate 8and the chair body 3 are fixedly connected. By adjusting the distancebetween the engaging block 6 and the cover plate 8, the compressionamount of the spring 5 is adjusted and the support force of the backrest1 can be adjusted correspondingly to meet different needs. In someapplications, a pneumatic mechanism, such as a vacuum cylinder, anairbag, a connecting block made of a material with a good resilienceproperty, and the like, can also be used.

In other embodiments, the compression amount of the spring 5 is adjustedas follows. As shown in FIG. 5 , an adjusting rod 7 is arranged on thecover plate 8 and rotatably connected with the cover plate 8, and theengaging block 6 is in threaded connection with the adjusting rod 7;that is, the distance between the engaging block 6 and the cover plate 8can be adjusted by rotating the adjusting rod 7, thereby adjusting thecompression amount of the spring 5 to adjust the support force. Inanother embodiment, a cam mechanism can also be configured to adjust thedistance between the engaging block 6 and the cover plate 8.

In some applications, the backrest adjusting mechanism further includesa locking mechanism. The locking mechanism is configured to fix theconnecting base 2 to keep a fixed distance from the chair body 3. Asshown in FIG. 1 , the locking mechanism includes a limit pin 4 which isslidably connected with a second sleeve 31; a first sleeve 201 isprovided with a plurality of limit holes to cooperate with the limit ofthe limit pin 4 for adjustment, which is convenient for operation.

In some applications, the backrest 1 is slidably connected to theconnecting base 2 and moves vertically up and down along the connectingbase 2. The connecting base 2 is provided with a height adjustingassembly, configured to adjust the height of the backrest 1 so thatpeople of different heights can use the chair; the position of thebackrest 1 can be adjusted according to the height of the user toprovide support for the waist.

Preferably, as shown in FIGS. 2 and 4 , the height adjusting assemblyincludes a swing rod 22 and a limit rod 221, a fan-shaped groove 211 isformed in a side of the connecting base 2 away from the backrest 1, andthe swing rod 22 is received in the fan-shaped groove 211. One end ofthe swing rod 22 is hinged with the connecting base 2, and a torsionspring is arranged at the hinged position to keep the swing rod 22 in avertical state; a groove 101 is formed in a side of the backrest 1 closeto the connecting base 2, a plurality of oblique tooth grooves 102 arearranged in an array in a vertical direction in the groove 101, thetooth groove direction of the oblique tooth grooves 102 faces downward,and the limit rod 221 is fixed on an end of the swing rod 22 away fromthe hinged position, and extends through the connecting base 2 to beinserted into one oblique tooth groove 102. When the position of thebackrest 1 needs to be raised, the backrest 1 is lifted up, and thelimit rod 221 slides into the next tooth groove along the tooth surfaceof the oblique tooth groove 102 to support the backrest 1, and a torsionspring arranged on the swing rod 22 keeps the limit rod 221 insertedinto one oblique tooth groove 102. When the backrest 1 moves so that thelimit rod 221 moves to a lowermost oblique tooth groove 102, the limitrod 221 is disengaged from the oblique tooth groove 102, and then thebackrest 1 can move downward.

In some applications, the backrest 1 is hinged with the connecting base2 through a pivot, and the backrest 1 swings in a vertical plane alongthe connecting base 2 within a set swing angle range. When the user'sbody swings from side to side, the backrest 1 moves too, which improvesthe user's experience comfort.

In some applications, the backrest 1 is provided with a rotating shaftalong a vertical direction, and the backrest 1 and the connecting base 2are hinged through the rotating shaft. When the user's body rotates fromside to side, the backrest 1 rotates together with the user to improvethe user's experience comfort.

In the description of this disclosure, it is to be understood that theorientations or positional relationships, indicated by the terms, suchas “upper”, “lower”, “left”, “right”, etc., are based on theorientations or positional relationships shown in the drawings and areonly for the purpose of facilitating and simplifying the description ofthis disclosure, rather than indicating or implying that the describeddevice or element must have a particular orientation or must beconstructed or operated in a particular orientation, and therefore theycannot to be construed as limiting this disclosure.

Moreover, the terms “first” and “second” are used for descriptivepurposes only and should not be construed as indicating or implying arelative importance or implicitly indicating the number of technicalfeatures indicated. In the description of this disclosure, “a pluralityof” means two or more two or, unless otherwise specifically defined.

For those skilled in the art, it can be understood that various changes,modifications, substitutions, and modifications can be made to theseembodiments without departing from the principle and spirit of thisdisclosure. Therefore, from any point, the embodiments should beregarded as instructive and non-restrictive. The scope of thisdisclosure is defined by the appended claims rather than the abovedescription. The preferred embodiments of this disclosure are notintended to limit this disclosure. Any modification, equivalentreplacement, improvement, etc. within the spirit and principle of thisdisclosure shall be included in the scope of this disclosure.

What is claimed is:
 1. A backrest adjusting mechanism, comprising abackrest (1), wherein the backrest (1) is movably arranged above asupport surface of a chair body (3), and a distance between the backrest(1) and a backrest support plate of the chair body (3) is adjustable;the backrest (1) is provided with a connecting base (2) on a side closeto the backrest support plate of the chair body (3), and the backrest(1) is movably connected with the connecting base (2); the backrestadjusting mechanism further comprises at least one set of slidingassembly, wherein the sliding assembly is configured to connect theconnecting base (2) and the backrest support plate of the chair body(3), the sliding assembly comprises a sliding block (11) and a slidingrail (12), the sliding block (11) is slidably connected with the slidingrail (12), the sliding block (11) is fixedly connected with theconnecting base (2), the sliding rail (12) is fixedly connected with thechair body (3), and the sliding rail (12) is provided with an anti-offcomponent for limiting the sliding block from falling off; the backrestadjusting mechanism further comprises an elastic member, arrangedbetween the connecting base (2) and the backrest support plate of thechair body (3).
 2. The backrest adjusting mechanism according to claim1, wherein the elastic member comprises a spring (5) having an endfixedly engaged with the connecting base (2) and an end fixedly engagedwith an engaging block (6), a distance between the engaging block (6)and a cover plate (8) is adjustable for adjusting a support force of thebackrest (1), and the cover plate (8) and the chair body (3) are fixedlyconnected.
 3. The backrest adjusting mechanism according to claim 2,wherein an adjusting rod (7) is arranged on the cover plate (8) androtatably connected with the cover plate (8), and the engaging block (6)is in threaded connection with the adjusting rod (7).
 4. The backrestadjusting mechanism according to claim 1, further comprising a lockingmechanism, the locking mechanism being configured to fix the connectingbase (2) to keep a fixed distance from the chair body (3).
 5. A chair,comprising the backrest adjusting mechanism according to claim 1, thebackrest (1) being slidably connected to the connecting base (2), thebackrest (1) moving vertically up and down along the connecting base(2), the connecting base (2) being provided with a height adjustingassembly, the height adjusting assembly being configured to adjust aheight of the backrest (1).
 6. The backrest adjusting mechanismaccording to claim 1, wherein the height adjusting assembly comprises aswing rod (22) and a limit rod (221), a fan-shaped groove (211) isformed in a side of the connecting base (2) away from the backrest (1),and the swing rod (22) is received in the fan-shaped groove (22); oneend of the swing rod (22) is hinged with the connecting base (2), and atorsion spring is arranged at the hinged position to keep the swing rod(22) in a vertical state; a groove (101) is formed in a side of thebackrest (1) close to the connecting base (2), a plurality of obliquetooth grooves (102) are arranged in an array in a vertical direction inthe groove (101), a tooth groove direction of the oblique tooth grooves(102) faces downward, and the limit rod (221) is fixed on an end of theswing rod (22) away from the hinged position, and extends through theconnecting base (2) to be inserted into one said oblique tooth groove(102).
 7. A chair, comprising the backrest adjusting mechanism accordingto claim 1, the backrest (1) being hinged with the connecting base (2)through a pivot, the backrest (1) swinging in a vertical plane along theconnecting base (2) within a set swing angle range.
 8. A chair,comprising the backrest adjusting mechanism according to claim 1, thebackrest (1) being provided with a rotating shaft along a verticaldirection, the backrest (1) and the connecting base (2) being hingedthrough the rotating shaft.